Since commit b14a0b7469f ("accel: Use QOM classes for accel types")
accelerators are registered as QOM objects. Use QOM as a generic
API to query for available accelerators. This is in particular
useful to query hardware accelerators such HFV, Xen or WHPX which
otherwise have their definitions poisoned in "exec/poison.h".

Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
---
 tests/qtest/libqtest.c | 21 ++++++++++-----------
 1 file changed, 10 insertions(+), 11 deletions(-)

diff --git a/tests/qtest/libqtest.c b/tests/qtest/libqtest.c
index 7e9366ad6d5..3071dedeff6 100644
--- a/tests/qtest/libqtest.c
+++ b/tests/qtest/libqtest.c
@@ -30,6 +30,7 @@
 
 #include "libqtest.h"
 #include "libqmp.h"
+#include "qemu/accel.h"
 #include "qemu/ctype.h"
 #include "qemu/cutils.h"
 #include "qemu/sockets.h"
@@ -1030,13 +1031,10 @@ static bool qtest_qom_has_concrete_type(const char *parent_typename,
 
 bool qtest_has_accel(const char *accel_name)
 {
-    if (g_str_equal(accel_name, "tcg")) {
-#if defined(CONFIG_TCG)
-        return true;
-#else
-        return false;
-#endif
-    } else if (g_str_equal(accel_name, "kvm")) {
+    static QList *list;
+    g_autofree char *accel_type = NULL;
+
+    if (g_str_equal(accel_name, "kvm")) {
         int i;
         const char *arch = qtest_get_arch();
         const char *targets[] = { CONFIG_KVM_TARGETS };
@@ -1048,11 +1046,12 @@ bool qtest_has_accel(const char *accel_name)
                 }
             }
         }
-    } else {
-        /* not implemented */
-        g_assert_not_reached();
+        return false;
     }
-    return false;
+
+    accel_type = g_strdup_printf("%s%s", accel_name, ACCEL_CLASS_SUFFIX);
+
+    return qtest_qom_has_concrete_type("accel", accel_type, &list);
 }
 
 bool qtest_get_irq(QTestState *s, int num)
-- 
2.47.1

On 2025/01/28 20:18, Philippe Mathieu-Daudé wrote:
> Since commit b14a0b7469f ("accel: Use QOM classes for accel types")
> accelerators are registered as QOM objects. Use QOM as a generic
> API to query for available accelerators. This is in particular
> useful to query hardware accelerators such HFV, Xen or WHPX which
> otherwise have their definitions poisoned in "exec/poison.h".
> 
> Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
> ---
>   tests/qtest/libqtest.c | 21 ++++++++++-----------
>   1 file changed, 10 insertions(+), 11 deletions(-)
> 
> diff --git a/tests/qtest/libqtest.c b/tests/qtest/libqtest.c
> index 7e9366ad6d5..3071dedeff6 100644
> --- a/tests/qtest/libqtest.c
> +++ b/tests/qtest/libqtest.c
> @@ -30,6 +30,7 @@
>   
>   #include "libqtest.h"
>   #include "libqmp.h"
> +#include "qemu/accel.h"
>   #include "qemu/ctype.h"
>   #include "qemu/cutils.h"
>   #include "qemu/sockets.h"
> @@ -1030,13 +1031,10 @@ static bool qtest_qom_has_concrete_type(const char *parent_typename,
>   
>   bool qtest_has_accel(const char *accel_name)
>   {
> -    if (g_str_equal(accel_name, "tcg")) {
> -#if defined(CONFIG_TCG)
> -        return true;
> -#else
> -        return false;
> -#endif
> -    } else if (g_str_equal(accel_name, "kvm")) {
> +    static QList *list;
> +    g_autofree char *accel_type = NULL;
> +
> +    if (g_str_equal(accel_name, "kvm")) {
>           int i;
>           const char *arch = qtest_get_arch();
>           const char *targets[] = { CONFIG_KVM_TARGETS };
> @@ -1048,11 +1046,12 @@ bool qtest_has_accel(const char *accel_name)
>                   }
>               }
>           }
> -    } else {
> -        /* not implemented */
> -        g_assert_not_reached();
> +        return false;
>       }
> -    return false;
> +
> +    accel_type = g_strdup_printf("%s%s", accel_name, ACCEL_CLASS_SUFFIX);

g_strconcat() will make this a bit shorter.

> +
> +    return qtest_qom_has_concrete_type("accel", accel_type, &list);
>   }
>   
>   bool qtest_get_irq(QTestState *s, int num)

On 28/01/2025 12.18, Philippe Mathieu-Daudé wrote:
> Since commit b14a0b7469f ("accel: Use QOM classes for accel types")
> accelerators are registered as QOM objects. Use QOM as a generic
> API to query for available accelerators. This is in particular
> useful to query hardware accelerators such HFV, Xen or WHPX which
> otherwise have their definitions poisoned in "exec/poison.h".
> 
> Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
> ---
>   tests/qtest/libqtest.c | 21 ++++++++++-----------
>   1 file changed, 10 insertions(+), 11 deletions(-)
> 
> diff --git a/tests/qtest/libqtest.c b/tests/qtest/libqtest.c
> index 7e9366ad6d5..3071dedeff6 100644
> --- a/tests/qtest/libqtest.c
> +++ b/tests/qtest/libqtest.c
> @@ -30,6 +30,7 @@
>   
>   #include "libqtest.h"
>   #include "libqmp.h"
> +#include "qemu/accel.h"
>   #include "qemu/ctype.h"
>   #include "qemu/cutils.h"
>   #include "qemu/sockets.h"
> @@ -1030,13 +1031,10 @@ static bool qtest_qom_has_concrete_type(const char *parent_typename,
>   
>   bool qtest_has_accel(const char *accel_name)
>   {
> -    if (g_str_equal(accel_name, "tcg")) {
> -#if defined(CONFIG_TCG)
> -        return true;
> -#else
> -        return false;
> -#endif
> -    } else if (g_str_equal(accel_name, "kvm")) {
> +    static QList *list;
> +    g_autofree char *accel_type = NULL;
> +
> +    if (g_str_equal(accel_name, "kvm")) {
>           int i;
>           const char *arch = qtest_get_arch();
>           const char *targets[] = { CONFIG_KVM_TARGETS };
> @@ -1048,11 +1046,12 @@ bool qtest_has_accel(const char *accel_name)
>                   }
>               }
>           }
> -    } else {
> -        /* not implemented */
> -        g_assert_not_reached();
> +        return false;
>       }
> -    return false;
> +
> +    accel_type = g_strdup_printf("%s%s", accel_name, ACCEL_CLASS_SUFFIX);
> +
> +    return qtest_qom_has_concrete_type("accel", accel_type, &list);
>   }

Nice!

Reviewed-by: Thomas Huth <thuth@redhat.com>